From: Tejun Heo <tj@kernel.org>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Christoph Lameter <cl@linux.com>,
Eric Dumazet <eric.dumazet@gmail.com>,
akpm@linux-foundation.org, Pekka Enberg <penberg@cs.helsinki.fi>,
linux-kernel@vger.kernel.org,
Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Subject: Re: [cpuops cmpxchg V2 5/5] cpuops: Use cmpxchg for xchg to avoid lock semantics
Date: Tue, 14 Dec 2010 18:29:00 +0100 [thread overview]
Message-ID: <4D07A95C.7030703@kernel.org> (raw)
In-Reply-To: <4D07A7CB.7010205@zytor.com>
Hello,
On 12/14/2010 06:22 PM, H. Peter Anvin wrote:
> On 12/14/2010 09:19 AM, Christoph Lameter wrote:
>>>
>>> Is it genuinely faster to do the pre-load mov, or can we drop that too?
>>> My guess would be that yes it is, but if it happens not to be it would
>>> be nice to reduce the code size.
>>
>> Dropping the load increases the cycle count from 11 to 16.
>
> Great, that answers that! I'll pick up the patch hopefully today (I'm
> finally ramping back up on arch/x86 again after having been diverted to
> an internal project for a while...)
How do you want to route these? All patches before this series is
already in the percpu tree. I can pull the generic bits and leave out
the x86 bits so that x86 tree can pull in percpu bits and then put x86
stuff on top of it. If you wanna go that way, I would drop all x86
related patches from the previous patchsets too.
Thanks.
--
tejun
next prev parent reply other threads:[~2010-12-14 17:30 UTC|newest]
Thread overview: 49+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-12-14 16:28 [cpuops cmpxchg V2 0/5] Cmpxchg and xchg operations Christoph Lameter
2010-12-14 16:28 ` [cpuops cmpxchg V2 1/5] percpu: Generic this_cpu_cmpxchg() and this_cpu_xchg support Christoph Lameter
2010-12-17 14:55 ` Tejun Heo
2010-12-14 16:28 ` [cpuops cmpxchg V2 2/5] x86: this_cpu_cmpxchg and this_cpu_xchg operations Christoph Lameter
2010-12-17 15:22 ` Tejun Heo
2010-12-14 16:28 ` [cpuops cmpxchg V2 3/5] irq_work: Use per cpu atomics instead of regular atomics Christoph Lameter
2010-12-15 16:32 ` Tejun Heo
2010-12-15 16:34 ` H. Peter Anvin
2010-12-15 16:50 ` Peter Zijlstra
2010-12-15 17:04 ` Christoph Lameter
2010-12-15 17:18 ` Peter Zijlstra
2010-12-15 17:31 ` H. Peter Anvin
2010-12-15 17:32 ` Christoph Lameter
2010-12-18 15:32 ` Tejun Heo
2010-12-14 16:28 ` [cpuops cmpxchg V2 4/5] vmstat: User per cpu atomics to avoid interrupt disable / enable Christoph Lameter
2010-12-15 16:45 ` Tejun Heo
2010-12-15 17:01 ` Christoph Lameter
2010-12-14 16:28 ` [cpuops cmpxchg V2 5/5] cpuops: Use cmpxchg for xchg to avoid lock semantics Christoph Lameter
2010-12-14 16:35 ` Mathieu Desnoyers
2010-12-14 16:44 ` Eric Dumazet
2010-12-14 16:55 ` Christoph Lameter
2010-12-14 17:00 ` H. Peter Anvin
2010-12-14 17:19 ` Christoph Lameter
2010-12-14 17:22 ` H. Peter Anvin
2010-12-14 17:29 ` Tejun Heo [this message]
2010-12-14 17:35 ` Christoph Lameter
2010-12-15 1:06 ` H. Peter Anvin
2010-12-15 16:29 ` Tejun Heo
2010-12-15 16:35 ` H. Peter Anvin
2010-12-15 16:39 ` Tejun Heo
2010-12-16 16:14 ` Tejun Heo
2010-12-16 18:13 ` x86: Use this_cpu_has for thermal_interrupt Christoph Lameter
2010-12-18 15:35 ` Tejun Heo
2010-12-21 0:56 ` H. Peter Anvin
2010-12-30 11:29 ` Tejun Heo
2010-12-30 18:19 ` H. Peter Anvin
2010-12-31 12:43 ` Tejun Heo
2010-12-16 18:14 ` x86: udelay: Use this_cpu_read to avoid address calculation Christoph Lameter
2010-12-16 18:15 ` gameport: use this_cpu_read instead of lookup Christoph Lameter
2010-12-18 15:34 ` Tejun Heo
2010-12-16 18:16 ` acpi throttling: Use this_cpu_has and simplify code Christoph Lameter
2010-12-18 15:50 ` Tejun Heo
2010-12-21 1:52 ` ykzhao
2010-12-21 22:43 ` Christoph Lameter
2010-12-21 4:28 ` Len Brown
2010-12-16 18:19 ` [cpuops cmpxchg V2 5/5] cpuops: Use cmpxchg for xchg to avoid lock semantics H. Peter Anvin
2010-12-16 18:55 ` Tejun Heo
2010-12-16 20:42 ` H. Peter Anvin
2010-12-15 16:47 ` Tejun Heo
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